小冰期福建海岸沙丘的沉积环境  

Sedimentary Environment of Little Ice Age Recorded by A Coastal Aeolian Dune in Fujian,China

作　　者：靳建辉[1] 李志忠[1] 

机构地区：[1]福建师范大学地理研究所/地理科学学院/湿润亚热带生态-地理过程教育部重点实验室,福建福州350007

出　　处：《中国沙漠》2017年第6期1111-1120,共10页Journal of Desert Research

基　　金：国家自然科学基金项目(41271031;41301012);国家自然科学基金委员会-福建省人民政府促进海峡两岸科技合作联合基金项目(U1405231);福建省自然科学基金项目(2017J01460)

摘　　要：选取福建东南沿海典型海岸沙丘——东海沙丘,运用GPR(Ground Penetrating Radar)技术探测海岸沙丘内部构造,辅助天然剖面和人工探槽观测,进行系统的年代采样与OSL(Optically Stimulated Luminescence)测年,并选择物理意义明确的粒度参数作为主要环境代用指标,获得了亚热带季风区砂质海岸带典型海岸沙丘的沉积年代和沉积结构。结果表明:(1)东海沙丘是由若干灌丛沙丘组成的横向沙丘,0~6m主要是~0.45ka BP以来形成的海岸风成沙丘,可以划分为~0.45ka BP和0.22~0.12ka BP两个阶段。(2)东海沙丘沉积过程是多因素共同作用的结果,冷干的气候环境是沙丘发育的适宜条件,入境台风频率增加可能加快了风沙的沉积过程。对比历史文献资料发现,气候异常期往往与社会动荡期、重要历史事件相对应。Coastal aeolian dune is a typical type of aeolian landform in coastal zone of South China.The imformation of development history and paleoenvironment were well recorded in the sediment of coastal aeolian dune.The aim of this article is to understand the formation process of coastal aeolian dune and analyze the relationship between human activities and environmental evolution since Little Ice Age.In this study,a coastal aeolian dune（DH）of 0-6 m depth in Changle,Fujian,China,was selected as a research object.Optically stimulated luminescence（OSL）technique was selected to establish the chronological framework of this aeolian dune.Combined with grain-size parameters and geological radar images,the dune development history and paleoenvironment significance in the study area during the last 450 years were explored.Results are shown as follows.（1）DH dune（0-6 m）is a coastal aeolian transversal dune,which are made up of several shrub dunes since about 450 a BP.（2）The deposition rate of DH dune is affected by integrated factors,such as East Asia Summer Monsoon（rainfall）intensity,East Asia Winter Monsoon intensity.It also is significantly associated with the winter temperature,typhoon frequency and vegetation coverage.The cold-dry climate is the suitable condition of wind-sand activity.Meanwhile,the periods of climate abnormality are usually associated with social turbulence and important historical events.

关 键 词：海岸沙丘 光释光年代学 小冰期 环境演变 

分 类 号：P531[天文地球—古生物学与地层学]